o< 



The exopodites of the 1st abdominal appendages are of extraordinary 

 length, being longer than the first b\ abdominal terga combined. 



The " thelycnm " is a narrow and very acute plate situated between the 

 4th pair of legs, and is followed by an elongate-oval tubercle situated between the 

 5th pair. In the male there are two spines which correspond with the 2 portions 

 of the thelycnm. 



The "andricum" is a pair of loosely-interlocking, trnncate-triangnlar plates. 



In both sexes the sterna of the first 3 abdominal somites are produced, 

 between the coxa? of their appendages, into very strong vertical nncate 

 processes. 



Colour in life, deep crimson. 



In a large female the carapace and rostrum measure 112 millim., and the 

 abdomen measures 114 millim. in the mid-dorsal line. The male grows to the 

 same size as the female, though the rostrum is always shorter. 



Arabian Sea near the Malabar coast 430 fathoms, Gulf of Manar 597 and 

 457-589 fathoms, Bay of Bengal 475 fathoms, Andaman Sea 188-220 and 271 

 fathoms. 



E-i -vr 8556 8558 

 egd. Nos. — : — : 



16. Aristceus (Plesiopeneus) coruscans, Wood-Mason. 



Aristseus coruscans, Wood-Mason, Ann. Mag. Xat. Hist., Oct. 1S91, p. 280, tig. 6. 

 Illustrations op the Zoology of the Investigator, Crustacea, Plate II. Fig. 3. 



Differs from Aristasm (Plesioponeus) edwardsianus only in the following 

 particulars : — 



Rostrum in the female much longer than the carapace, its carina distinct 

 and sharp to within a short distance of the posterior border of the carapace, 

 its second tooth is placed far in advance of the orbital border. Cervical groove 

 fine but very distinct. (The grooves and ridges are prominent as in the preced- 

 ing species). 



Only the last three abdominal terga are carinated, all the carina? ending 

 in a spine. The 6th abdominal somite is slightly more than twice the length 

 of the 5th. The abdominal pleura are not mucronate at the postero-lateral 

 angle. 



The tubercle of the eyestalk is very distinct. The antennal scale reaches 

 a good way beyond the antennular peduncle : it is not prolonged into a long 

 fleshy flagellum in the male. 



The terminal joint of the mandibular palp is subtriangular. The exopodite 

 of the 2nd maxillipeds, though long, is not nearly twice the length of the endopo- 



